Inducing air

ABSTRACT

A mechanism configured to interact with air, which has been sucked through a device that imparts turbulence to the air, causes a redistribution of components (e.g., oxygen and nitrogen) in the air so that when the air arrives at a location where the oxygen is to be consumed there is an enriched supply of oxygen available. The effects of a first stage of turbulence of the induced air is reduced, resulting in a higher density supply to the atomization point and to the combustion chamber, in the case of an internal combustion engine.

CLAIM OF PRIORITY

This application is a continuation of U.S. patent application Ser. No.11/373,838, filed Mar. 10, 2006, which is a continuation of U.S. patentapplication Ser. No. 10/423,576, filed Apr. 25,2003, now U.S. Pat. No.7,189,273. The contents of all applications are hereby incorporated byreference in their entirety.

BACKGROUND

This invention relates to Inducing Air.

In an internal combustion engine, for example, induced air from theambient is mixed with fuel prior to combustion. Good combustion can beachieved if the induced air is homogeneous and the fuel-air mixture hasa particular ratio.

As shown in FIG. 1, air is induced into an engine 10 of a typicalautomobile along an induction pathway that includes a breathing port 12,an air filtration system 14 within a housing the expansion room 15,intake port 16, tubing 18 leading to a throttle body 20 (shownschematically), to the atomization point, 21, where fuel injectors sprayfuel into the induced air which is atomized within the induced air.Tubing 22 feeds the atomized fuel-air mixture from the atomization pointinto the combustion chambers 24 of the cylinders 26, where it is ignitedby spark plugs 28 controlled by a timing mechanism 30.

The efficiency of the engine depends on the amount of oxygen that isavailable from the induced air to mix with the fuel at the point ofatomization. The ambient air, and thus the induced air, contains about21% oxygen and 78% nitrogen. A typical engine is designed to use anair/fuel ratio of about 1 to 14 by weight at the point of atomization.

As shown also in FIG. 2, the ambient air is inducted by the suction ofthe engine vacuum acting through the air filter 14 (which removesparticles from the air) and into air expansion chamber 15, and throughintake port 16, and through the piping 18 and an intake manifold 17 thatlies along the length of the engine next to the intake ports 19 of thecylinders. The sucking occurs in cycles as each cylinder in turnundergoes an intake stroke as the piston is drawn away from itsassociated intake port 19. The cycling causes the air to be induced andto arrive at the intake manifold in successive bursts 30. The separationbetween successive bursts is smaller the higher the revolutions perminute (RPM) of the engine as selected by the driver using the throttlepedal. The timing between successive intake strokes also depends on theRPM. During the intake stroke of a given cylinder, one of the bursts ofair is located at the right position along the intake manifold to bedrawn into the atomization point 21 for mixture with the fuel.

SUMMARY

In general, in one aspect, the invention features, an apparatus thatincludes a mechanism configured to interact with air, which has beensucked through a device that imparts turbulence to the air, to cause aredistribution of components in the air so that when the air arrives ata location where the oxygen is to be consumed there is an enrichedsupply of oxygen available.

Implementations of the invention may include one or more of thefollowing features. The mechanism is configured to impart centrifugalforce to the components and the components are characterized bydifferent masses. The mechanism comprises deflection surfaces. Themechanism comprises a set of deflection surfaces arranged in a suctionpath along which the air is being sucked. The device comprises an airfilter. The mechanism is also configured to be mounted within an air boxhaving an air inlet served by the device that imparts turbulence. Themechanism comprises a set of vanes configured to spin the air that hasbeen sucked through the device. Each of the vanes is arranged at anangle to a path along which the air is being sucked. The vanes arearranged around a central point to form a spinner. At least some of thevanes are mounted so that an angle formed between the vanes and a pathalong which the air is being sucked varies with the force of sucking.The vanes comprise airfoils. The vanes are configured to causecomponents of the air having higher masses to move radially away from apath along which the air is being sucked. The vanes are configured tocause components of the air having lower masses to move radially towarda path along which the air is being sucked.

The device comprises an air filter. The air filter and the mechanism tocause redistribution of the components of the air are connected in asingle unit. The air filter and the mechanism are connected with a gapbetween them. The gap is between 1 and 10 mm. The air filter and themechanism are connected so that a gap between them fluctuates with thedegree of the sucking force. The air filter and the mechanism areconnected using a flexible skirt. The air filter comprises an automotiveair filter and the mechanism comprises an air spinner.

The apparatus includes an air box. The mechanism is supported within theair box. The mechanism is supported at a predetermined distance from anoutlet of the air box. The air box includes an outlet. The mechanism isconfigured to redistribute the components so that oxygen reaches theoutlet before nitrogen. The mechanism has an axis and the outlet isaligned with the axis. The mechanism has an axis and the outlet is notaligned with the axis. The air box includes exhaust openings to removeat least some components of the air other than oxygen. The exhaustopenings include pressure-operated valves. The air box includes astructure configured to select air to be drawn into the air box based onthe temperature of the air.

In general, in another aspect, the invention features an automotive airfilter comprising a filter material supported by a frame and deflectingvanes supported by the frame.

In general, in another aspect, the invention features a methodcomprising, at a place downstream of a device that imparts turbulence toa flow of air that is being sucked through the device on its way to alocation where oxygen in the air is to be consumed, redistributingcomponents of the air so that when the air arrives at the location wherethe oxygen is to be consumed there is an enriched supply of oxygenavailable.

Implementations of the invention may include one or more of thefollowing features. The redistributing of the components includesimparting centrifugal force to separate components of the air based ontheir relative masses. The redistributing of the components includesspinning the air that is sucked through the device. The spinningcomprises deflecting the air on deflection surfaces. The components ofthe air are redistributed beginning at no more than a small distancefrom the device through which the air is being sucked. The devicethrough which the air is being sucked comprises an air filter. Thelocation at where the oxygen is to be consumed comprises an atomizationpoint in an internal combustion engine. The components of the aircomprise oxygen and nitrogen. The redistribution of the componentscomprises causing at least one of the components to tend to occupy acentral cylindrical region and at least another of the components totend to occupy a cylindrical shell around the central cylindricalregion.

The oxygen tends to occupy the central cylindrical region. The oxygentends to occupy the cylindrical shell.

In general, in another aspect, the invention features a methodcomprising increasing availability at a downstream location in an engineof oxygen contained in a supply of air by mechanically separating oxygenand nitrogen at an upstream position in an air induction path leadingfrom an intake filter to the downstream position.

In general, in another aspect, the invention features apparatuscomprising an internal combustion engine, an induction pathway from asource of ambient air to the engine, a filter in the induction pathway,and a structure of deflecting vanes attached to the air filter todeflect air that has been sucked through the filter.

In general, in other aspects, the invention features methods of makingair filters that include deflection vanes, methods of installingdeflection vanes, and methods of making air boxes that includedeflection vanes.

In general, in another aspect, the invention features an apparatus thatincludes an internal combustion engine, an induction pathway from asource of ambient air to the engine, a filter in the induction pathway,and a structure of deflecting vanes attached to the air filter todeflect air that has been sucked through the filter.

In general, in other aspects, the invention features apparatus thatincludes a mechanism configured to interact with air, which has beensucked through a device that imparts turbulence to the air, by (1)reducing a stage of low-amplitude, high-frequency turbulence imparted tothe air as it is being sucked through the device, (2) causing areduction in effects that are due to bands of turbulence produced in theair by stroking of an internal combustion engine, and/or (3) causing areduction in effects that are due to phase shifts within bands ofturbulence produced by in the air by stroking of an internal combustionengine.

Implementations of the invention may include one or more of thefollowing features. The vanes are configured to cause components of theair having lower masses to move radially away from a path along whichthe air is being sucked. The vanes are configured to cause components ofthe air having higher masses to move radially toward a path along whichthe air is being sucked. The exhaust openings include pressure-operatedvalves are supplemented by a suction enhancement device. The turbulenceis reduced by placing vanes in the air path for incidental losses.

In general, in another aspect, the invention features an apparatus thatincludes an internal combustion engine, an induction pathway from asource of ambient air to the engine, a filter in the induction pathway,a structure of deflecting vanes attached to the air filter to deflectair that has been sucked through the filter, and a mechanism to changethe angle of the deflecting vanes depending on the suction force, usingat least one of the suction force, a vacuum or an electrically-operatedactuator.

Other advantages and features will become apparent from the followingdescription and from the claims.

DETAILED DESCRIPTION

FIG. 1 shows a typical gasoline engine.

FIG. 2 shows an airflow pattern in an induction manifold.

FIG. 3 shows an effect of dust on a single pore of an air filter.

FIG. 4 shows an input and output velocity distribution along a reversenozzle.

FIG. 5 shows a graph of a critical Reynolds number versus a nozzlecontraction ratio

FIG. 6 shows air permeability of a reverse nozzle at differentvelocities.

FIG. 7 shows an air density distribution across a filter due to porenon-uniformity.

FIG. 8 shows build-up of turbulences in an engine cycle (4 inductionstrokes).

FIG. 9 shows a geometrical illustration of turbulence build-up.

FIG. 10 shows concentration of oxygen in the center and nitrogen at theperiphery (for center air intake).

FIG. 11 shows a concentration of nitrogen in the center and oxygen atthe periphery (for side air intake).

FIG. 12A shows a spinner placement.

FIG. 12B shows a high molecular collision and crossover zone.

FIG. 12C shows a top view of self-adjusting spinner height.

FIG. 12D shows a side view of self-adjusting spinner height.

FIG. 12E shows airflow channels.

FIG. 12EA (also referred to as 12F in the text) shows combustion andpower profiles for a high turbulence air supply

FIG. 12EB (also referred to as 12G in the text) shows combustion andpower profiles for a low turbulence air supply.

FIG. 12F (also referred to as 12H in the text) shows an air intake portwith 1 to 2 cm clearance.

FIG. 12G (also referred to as 12I in the text) shows an air intake portwith 2 to 5 cm clearance.

FIG. 12H (also referred to as 12J in the text) shows an air intake portwith more than 5 cm clearance.

FIG. 13A shows a vane arrangement for concentrating oxygen in thecenter.

FIG. 13B shows a vane arrangement for concentrating oxygen in theperiphery.

FIG. 13C shows a suction force range at low RPM.

FIG. 13D shows a suction force range at high RPM.

FIG. 14A shows an air box with central intake.

FIG. 14B shows an air box with periphery intake.

FIG. 15A shows a self-adjusting vane angle.

FIG. 15B shows a mechanism to reduce nitrogen.

FIG. 16 shows separation of oxygen and nitrogen.

FIG. 17A shows formation of a bubble in the intake tube.

FIG. 17B shows an oscillating range of nitrogen.

FIG. 18A shows dead zones between strokes with respect to time

FIG. 18B shows dynamics of a nitrogen bubble between strokes.

FIG. 18C shows an absolute time representation of dead zones.

FIG. 19 shows a mechanism to maintain intake air temperature.

FIG. 20A shows a top view of a spinner concentrating oxygen in center.

FIG. 20B shows a side view of a spinner concentrating oxygen in center.

FIG. 20C shows a cross-sectional view of spinner concentrating oxygen incenter.

FIG. 21A shows a top view of a spinner concentrating oxygen inperiphery.

FIG. 21B shows a side view of a spinner concentrating oxygen inperiphery

FIG. 21C shows across-sectional view of a spinner concentrating oxygenin periphery.

FIG. 22 shows a spinner part of the filter box assembly.

FIG. 23 shows a schematic side view of a spinner.

FIG. 24 is a schematic view of an intake path.

Apparently, designers of the air filter 14 and the piping 18 leading tothe intake manifold have assumed that the air that is sucked through theair filter and the piping will inherently maintain the sameoxygen/nitrogen profile (that is, the relatively random positions ofnitrogen and oxygen molecules in the ambient air) as in the originalambient state before being induced.

On that assumption, the desired amount of oxygen is expected to beavailable at the moment of, and at the point of atomization, so that theair/fuel mixture will produce the designed level of efficiency inoperation of the engine.

Yet a close analysis of the airflow within the induction system suggeststhat the assumption is likely wrong, for the following reasons.

An air filter is typically made of a paper or synthetic material thathas a non-uniform distribution of pores. The material is pleated toincrease the surface area through which the inducted ambient air willflow. Both the non-uniform pore distribution and the pleating contributeto non-uniformity in the velocity distribution of the air across theoutput surface area of the filter. This non-uniformity of the velocitydistribution at the output surface imparts at least two importanteffects to the characteristics of the induced air when it eventuallyreaches the point of atomization.

One effect is a high degree of turbulence in the induced air at thepoint of atomization. The other effect is a randomness in the density ofair at the point of atomization caused by the high and low density bandsof air along the length of the induction piping produced by successivesuction cycles along the induction path, as explained below.

The turbulence is also increased by the pressure differences that arecreated between the input side and output side of the filter as theengine strokes.

The increased turbulence in the air on the output side of the air filteris attributable in part to the mode in which the pores of the filtermaterial operate to pass air from the input side to the output side. Asthe engine strokes suck air through the filter material, particles inthe air are trapped on the input surface of the filter in the vicinityof each of the pores, in particular around the entrance of the airchannel that conducts air through the pore.

As shown in FIGS. 3A and 3B, which illustrate a single pore 40schematically in cross-section, the collection of these particles 42tends to cause the pore to act as a nozzle 44 operating in an oppositemode from the usual mode of a nozzle. In the normal mode of operation ofa nozzle, relatively turbulent air enters through a wide entrance, flowsthrough the contraction of the nozzle, loses some of its turbulence, andthen jets out the narrower exit in a relatively laminar form with ahigher velocity. For a nozzle in the reverse mode, as in FIGS. 3A and3B, the opposite is true. The air is received at a relatively highervelocity, loses its relative laminar form, loses some of its velocity,and exits into the vacuum with a relatively higher turbulence. Thisturbulence, in addition with the turbulence introduced due tointer-molecular collisions at the output ends of the reverse nozzles, isreferred to as the “first level turbulence” in later paragraphs. This isa high frequency, low amplitude turbulence component of the air that issucked into the housing on the downstream side of the filter material.

This turbulent air is sucked into the housing on the downstream side ofthe filter material.

FIG. 4 illustrates a nozzle operated in reverse mode with air enteringfrom its narrow cross-section end (46) and exiting from its widercross-section end (47). Because of its gradually increasing crosssection (from left to right in the figure), the nozzle increases thevelocity non-uniformity in the air. The shape and dimensions of thenozzle determine the magnitudes of velocity and their non-uniformityacross the output side.

Assume that air enters with a velocity V1 (45) at one point of intakecross-section 46 and enters with a velocity V1+DV1 (51) at another pointof the same cross section.

Assume also that the pressure is constant at all points of the crosssection. At the exhaust cross section 47, the air velocities at the exitare V2 (48) and V2+DV2 (52). Applying Bernoulli's equations for thesetwo streamlines and neglecting the square values of DV1 and DV2, weobtain: V1*DV1=V2*DV2 or DV1=DV2*V2/V1. If the fractional velocities atthe nozzle inlet and outlet are a1=DV1/V1 and a2=DV2/V2, thensubstituting DV1 from above yields: a1=DV2 (V2/V1̂2)=DV2 (V2/(V2/n)̂2)=n̂2a2, where n=V2/V1 which is a fractional value and also equal to F1/F2,which is the contraction ratio of the nozzle measured in cross-sectionalarea F1 (49) and F2 (50) are the cross sectional areas of the input andoutput sides respectively, of the reverse nozzle.

Then a2=a1/n̂2. Thus the velocity variation at exhaust cross section 47is higher, because n̂2 is a fractional value, and the increase in thevelocity variation at cross section 47 will be accompanied by higherturbulence (that is, a greater variation of velocities) at the exhaustcross section 47.

The contraction ratios of the nozzles formed by the pores of an airfilter vary widely and the different contraction ratios appear in randomorder across the filter. The critical Reynolds number for a sphere as afunction of the contraction ratio n as measured by Homer is shown inFIG. 5. The increasing turbulence is established by the fact that thecritical Reynolds number decreases with decreasing contraction ratio.

In addition to the accumulation of particles on the input side of thefilter material, which constrains the size of the pore openings, asecond effect that forms nozzles is high differentials in pressurebetween the input (ambient) air side and the output side of the filter(where the pressure is negative). These high pressure differentialseffectively turn pores into nozzles because of the formation of highair-density regions around the edges 60 of the pore entrances 62 asshown in FIG. 6A. As illustrated in FIGS. 6B and 6C, as the enginesuction increases, the pressures along the sides of the pores will tendto equalize (FIG. 6B). This will be the most efficient working point forthe filter pores. As the engine speed further increases, the capacity ofthe pores tend toward their maximum and efficiency decreases again (FIG.6C).

As shown in FIG. 7, because of the random nature of the web of filtermaterial in which the pores are formed, the orientations of the axes 70,72, 74 of the nozzles vary.

The cross-sectional profiles of the turbulences in the molecules as theyexit a nozzle depends on the orientation of the axis of the nozzlerelative to the axis 76 of the suction that is pulling the moleculesthrough the nozzle. When the pore axis 70 is aligned with the suctionaxis, the variability in turbulence among the different molecules isrelatively low across the outlet of the nozzle, although the directionsof the flows of different molecules exiting the nozzle outlet varywidely. For a nozzle axis 72, 74 not aligned with the suction axis, themolecules are more turbulent at the outlet of the nozzle and have adistribution of velocities that varies from high to low across theoutlet. The air molecules will undergo acceleration along an axisdefined by the vector addition of the axis of suction and the axis ofthe pore, because of the pressure on the air due to the walls of thepore. Thus, there will be a high-density area closer to the suction axisand a low-density area away from it.

In the non-suction periods between the successive suctions that areassociated with the strokes of the cylinders of the engine, the suctionforce stops and no substantial amount of new ambient air is being drawnthrough the filter. However, the relatively higher density bursts of airthat were sucked through the filter in earlier strokes continue to move,due to momentum, along the air induction pathway, separated byrelatively lower density regions. And the molecules of the higherdensity regions are subjected to increasing turbulence during thenon-suction periods.

FIGS. 8 and 9 illustrate the turbulence states of successive bursts ofair that are generated at the output side of the air filter and movealong the air induction pathway toward the intake ports of the engine.Each burst undergoes increasing turbulence as it moves along theinduction pathway.

As shown, two representative filter pores 80, 82 have axes 84, 86 thatare not aligned with the suction axis 88. The velocity of the air ineach pore is higher along the side that is more upstream with respect tothe suction axis and the air along that side is of higher density As aresult, the burst of air at position 90 has a cross-section of velocityand density areas that depend on the orientations of the pores thatproduced it. The figure implies that the variation of density from highto low and to high again is strictly periodic across the burst of air,but the actual profile will depend on the random orientations of thepores from which the air burst is derived.

During the non-stroke period that follows its formation, the air burstat location 90 progresses along the induction pathway to occupy anintermediate position 91. At the next suction period, it will movefurther and occupy the succeeding position 92. During the next suctionperiod, the burst is pulled further along the induction pathway andacquires additional turbulence.

The additional turbulence is imparted as the higher density air regionstend to move faster and to diffuse because air flows from higher densityor pressure to lower density or pressure toward each other, thusentraining the slower moving lower density air. Thus, as an air burstreaches position 92 the variations of density across the burst areapproximately the converse of what they were at position 90. By the timeit reaches each successive position 94, 96, the airburst has undergoneadditional turbulence compared to the prior position and the positionsof the denser and less dense regions have undergone approximately, a180-degree phase shift in each case. The suction forces imparted by thesuccessive four strokes are shown schematically at the top of FIG. 8.

Although the bursts of air are shown as having strictly confinedboundaries on the upstream and downstream edges, in fact, there is amore gradual transition between each of the bursts and the adjacentlow-density regions.

Nitrogen molecules have a lower molecular weight than the oxygenmolecules. The same suction force is being applied to both. Thus,because acceleration=force/mass, the nitrogen molecules in the air willgain higher velocity in a given time (since velocity=acceleration*time),in the turbulence than will oxygen molecules. With each successivesuction cycle, nitrogen molecules undergo additional acceleration, andmove faster and thus keep leading and collapsing when the suction forcestops. Nitrogen, due to its lower mass, decelerates faster than oxygen,and thus can be thought of as collapsing in the path of flow around theoxygen molecules. Because the ratio of nitrogen molecules to oxygenmolecules is 4:1, it is thought that the nitrogen may form a barrierjust in front of the oxygen molecules.

Thus, it is believed that the pleated construction of the filter and theacceleration and deceleration of the air mass due to engine strokingcontinually introduces turbulences into the air and forces the nitrogento collapse around the oxygen. As the nitrogen and oxygen encounter eachdead zone, the oxygen with its higher momentum continues to move forwardbecause it experiences a lower deceleration effect than the nitrogen.The nitrogen decelerates faster and collides with the oxygen molecules.As a result nitrogen moves over and around the oxygen, surrounding it.Nitrogen is available in greater abundance, and there are 4 molecules ofnitrogen, which are available to surround the one molecule of oxygen.When the engine begins suction again, the nitrogen undergoes greateracceleration than the oxygen and again collides with the oxygen. In thisstage also, the nitrogen will move over the oxygen and this will resultin even more encapsulation of the oxygen molecules.

In FIG. 9, the zigzags 10 added to the arrows represent the turbulencefactor added after each stroke.

As each burst of air is subjected to another sucking cycle to draw italong the induction pathway and into the intake manifold, the nitrogenmolecules, which have now substantially encapsulated the oxygenmolecules, undergo additional increases in turbulences due to therib-like structure within the air box (that is, the housing for thefilter) which are typically present to impart strength to the box.

In the case of an automobile that uses direct intake (in which theambient air intake pipe opens directly to winds impinging on the frontof the automobile), the ambient air creates an even higher pressuredifferential between the input and output sides of the filter causing itto further restrict airflow through the nozzles. Consequently, theengine uses more fuel to compensate for the power losses occasioned bythe backpressure in the induction pathway, in order to maintain thevelocity of the car. This phenomenon is more significant when drivingagainst the high winds as illustrated in FIGS. 6B and 6C.

To summarize, the air filter is believed to impose turbulence on theambient air in several ways: the turbulence imposed at the nozzle outputimmediately adjacent to the output side of the filter; the dynamics ofthe engine when stroking either in the steady state or inacceleration/deceleration mode which causes a continuous change insuction force and in the duration of the dead zones between the strokes;and the effect of the rough surface of the inner walls of the filterhousing which adds further losses to the air velocities.

Each of these turbulences carries at least three different kinds ofrandom energies:

one kind similar to the white noise in radio frequencies, is due to thenon-uniformity of material and construction of the filter material; asecond kind due to the construction of the air box; and a third kind dueto the successive stroking of the engine. The bands of air progressingalong the induction path are in effect a waveform with a certaininstantaneous frequency. This wave becomes the carrier for the first andsecond turbulences (also waveforms) just as two waves that pass eachother result in a wave that is the sum of the components.

Further, it is believed that the concentration of nitrogen moleculesaround the oxygen molecules operates as a barrier to the mixing of thefuel with the oxygen at the atomization point and hence reduces theefficiency of combustion.

Flow control techniques downstream of the air filter can be applied thatare designed not only to work against the effect of the nitrogenmolecules blocking the oxygen molecules from combining with the fuel,but also to enhance the density of oxygen molecules that are availablefor mixing with the fuel at the atomization point. During the combustionprocess, this ready availability of oxygen will result in more efficientcombustion than if the techniques were not applied. These techniquesalso decrease the pressure differential between the input side and theoutput side of the filter.

One key technique is to alter the induction pathway in a manner thatcauses the nitrogen and oxygen molecules to be separated across thebroad cross-sectional profile that exists at a point near to thedownstream side of the filter and then to take advantage of theseparation to assure that a higher density of oxygen molecules areavailable to mix with fuel at the atomization point and that thenitrogen molecules are less of a barrier to that mixing.

The induction pathway can be altered in such a way that the nitrogenmolecules and the oxygen molecules undergo different modes of motionbecause of their different molecular weights, causing them to separatespatially and enabling the mix of nitrogen and oxygen at the atomizationpoint to be manipulated to achieve more efficient combustion.

One way to alter the pathway uses vanes (as shown in FIG. 10) (in someexamples, the vanes form a so-called passive spinner 120) that spin theair around the axis of suction and thus cause the nitrogen molecules,which have a lower molecular weight, generally to form a cylindricalouter shell 122 downstream of the vanes while the oxygen moleculesgenerally form a central column 124 within the shell. Spinning the airas it is sucked along the pathway imparts an outward force componentthat causes a larger outward acceleration of the nitrogen molecules thanof the oxygen molecules. If the relatively small diameter port 125 thatalready typically exists between the filter housing and the intakemanifold is positioned on the housing so that it draws air from thecenter column, the oxygen will be drawn to the intake manifold first126, followed by the nitrogen 127, thus offsetting some of the effectsof the nitrogen acceleration, and assuring that more oxygen is availableto mix with the fuel. The profile of the air mixture entering theinduction tube is believed to be somewhat spherical with oxygenmolecules in higher concentration on the outer portions of the sphereand nitrogen molecules in higher concentration on the inner portions ofthe sphere.

In other cases, the vanes can be arranged (see FIG. 11) to direct theoxygen molecules to the outer shell 130 and the nitrogen molecules tothe inner column 128 by causing an inwardly directed larger accelerationof the nitrogen molecules. Then, if the air is sucked from the shellrather than the core, the oxygen-richer portion of each burst 132 willreach the atomization point first.

Other arrangements of vanes may also be possible.

The choice of which type of vanes to use, how many to use, whatconfiguration they should have, and how to position them, will depend,for example, on the configuration of the air box and the location fromwhich the intake air is removed from the air box (see FIG. 12A), i.e.,the location where the intake port 140 is placed in the air box. The airbox 143 is often rectangular in configuration.

It is believed that as the air is sucked through the filter 142, at ahigh velocity, it flows out of the output side of the filter in multipledirections as described earlier. As it jets out of the filter pores,there is a crossover effect produced by the different fractionalvelocities of air molecules from the filter output. This effect forms aturbulent transition zone 144 just above the filter surface where theintensity of inter-molecular collisions is high. The thickness of thiszone depends on the pressure differentials between the input and outputof the filter pores. The spatial restriction imposed by the pleats maycontribute also. Experiments indicate that the thickness of thistransition zone ranges between 1 mm and 5 mm. When a spinner 135 isplaced so that the air is captured just above this transition zone, theobserved results are favorable.

It is desirable to capture the moving air between the transition zoneand the position where the second stage of turbulence is being producedpredominantly by the engine strokes. Although the first stage ofturbulence in the transition zone is also created indirectly by theengine stroke, the predominant turbulence-generating factor for thefirst stage of turbulence is the operation of the pores as reversenozzles as the air leaves the pores.

The first stage of turbulence, introduced by the reverse nozzle effectof filter pores, is a high-frequency, low-amplitude effect. The secondand third stages of turbulences, which are due to engine strokes and thefilter box housing are relatively low in frequency and high inamplitude. Those stages of turbulence are reduced at the compressionstaking place at intake port 16, throttle 20, and the air output port 19that leads into the combustion chamber, as shown in FIG. 2. By contrast,the first stage turbulent air component is carried all the way to theatomization point and into the combustion chamber. We believe, on thebasis of experimentation that the first stage of turbulence is one ofthe factors that lowers air density, and consequently, oxygen density inthe combustion chamber.

When the air is deflected from the vane surfaces, incidental losses willoccur. If the surfaces are smooth enough, some of the first-stageturbulent energies will transfer into incidental losses and the airexiting the spinner will carry less of the in first-stage turbulence.Therefore placing the spinner just above the transition zone to capturethe first-stage turbulence is believed to be important, so that thefirst-stage turbulence does not become part of the second-stageandthird-stage progression of turbulences.

FIGS. 12F and 12G show anticipated combustion and power profiles as afunction of time in cases of a high first-stage turbulence air supplyand a low first-stage turbulence air supply, i.e., when a spinner isused. As shown, the high-turbulence air supply 1202 will result in acertain amount of combusted fuel 1212 and this combusted fuel willresult in the converted power 1220. The fuel that will remainuncombusted 1208 will result in unutilized power 1222.

FIG. 12G shows the corresponding components for a low-turbulence airsupply 1200, combusted fuel 1210, uncombusted fuel 1206. The power curveshows converted energy 1216 and unutilized energy 1218. We believe thatthe amount of fuel that will be combusted is greater in this case, as isthe converted energy.

The typical distance for placement of the spinner (called the “gapspacing” below) is between about 1 mm to 5 mm, depending on the filterand air box designs. The gap spacing is measured between the bottomedges of the spinner vanes and the top edges of the pleats of thefilter. Favorable gap spacings can be determined experimentally.

If the spinner is placed in the transition zone, the spinner isrelatively ineffective. Experiments showed that putting the spinner tooclose to the filter reduced gasoline mileage. We have found that it isdesirable to place the spinner far enough away from the upper edges ofthe filter pleats so that the air that is striking the spinner vanes isin a state just before the second stage of turbulence.

Factors that seem to affect the choice of a good gap spacing include thefilter material pore density and the number of pleats in the filter,which vary from manufacturer to manufacturer, and the amount ofclearance between the filter and the intake port within the air box. Forair boxes in which the clearance is high, the gap spacing may be withinthe range of 1 mm to 5 mm. Air boxes with higher clearances allow moreexpansion room for the incoming air and need a larger gap spacing.

An alternative mounting can be designed to take the dynamic variation ofthickness of the turbulent zone into account (as shown in FIGS. 12C and12D). The changing suction pressure of the engine causes changes in theexit velocities of molecules from the filter pores. These moleculesbuild up a small variable pressure outline over the filter surface justbefore going into the turbulence zone, and the height of the turbulencezone changes according to the change in suction force.

If the spinner is mounted on a flexible skirt material 145 attached to aframe 137, which will re-adjust the height 146 (see FIG. 12D) of thespinner above the filter surface in proportion to the thickness of theturbulence zone, the efficient range of operation of the spinner will befurther enhanced. In some examples, the flexible skirt will permit thegap spacing to fluctuate between approximately 1 mm and 5 mm in responseto pressure change, which has been found to improve the mileage.

FIG. 12E shows a typical vane 149 (or fin) used in the spinner. Thediagrammed vane is designed to create a velocity component of largermagnitude 1141 along the outside, and a velocity component of lowermagnitude 1143 along the inside of the vane. Thus, in terms of fluidpermeability, the permeability of the diagrammed vane is higher alongthe peripheral area 148 and lower toward the center 147. Because of thedifference in molecular weights, the nitrogen molecules will thus bedeflected toward the outside of the vane and will form a zone of highernitrogen concentration 148. The oxygen molecules will gather around thearea of the lower velocity component and will form a zone of higheroxygen concentration 147. As has been described earlier, a vane thatcreates the opposite effect can also be used. In such case, the oxygenabundant area will be on the outside and the nitrogen abundant area willbe on the inside of the vane. The location of the port inside the airbox determines which design is to be used.

FIGS. 12H, 12I and 12J show the variation of angle of inclination of thevanes of a spinner for different air boxes. The angle of inclination ofthe vanes are dependent upon the clearance between the top of thespinner and the air intake port within the air box. For air boxes withlower clearance, a smaller angle results in better efficiency. For airboxes with larger clearances, the angle of inclination has to beincreased.

In the figures, 12H, 12I and 12J, the x-axis is perpendicular to theaxis of suction, which is indicated as the negative y-axis. The angle ofinclination 151 indicates the angle between the plane of the surface ofthe spinner vane 145. The vane itself is not planar; rather, it is athree-dimensional airfoil with a curvature that can be considered to beformed along a median plane 153. The angle of inclination is themeasured angle between this median plane of the vane and the x-axis.There are many possible configurations and designs to set the pathwaysfor separation of the oxygen and the nitrogen. In some examples, theairfoils have a simple shape. In other examples, they are similar toblades of a commercial fan in testing our hypothesis. While both haveshown positive results, we believe that neither of them may be the mostefficient design for separation.

If an airfoil were designed specifically for the purpose of separationtaking the airflow characteristics in an automobile air box intoaccount, higher efficiency may result.

The angle of inclination for either an outward spinner or an inwardspinner is chosen as a function of the clearance 152 between the airintake port inside the air box and the inside filter surface.

Referring to FIGS. 12H, 12I, and 12J, different incident vane angles ofdifferent spinners will create different airflow patterns. Thus, theprofiles of the oxygen and nitrogen zones at the level at which the airintake port is placed in the air box will vary. It is useful to choose aspinner with a vane angle that produces an optimal separation of oxygenand nitrogen at the location of the air intake port. By doing so, higherefficiency will be achieved. Typical angles for good efficiency arebetween 35 and 45 degrees from the horizontal surface of the filter.FIG. 13A and FIG. 13B show spinners having four vanes 155 each. For eachspinner, each of the vanes has a planar surface that is at the selectedangle of inclination chosen to be suitable for the air box for which itis designed. FIG. 13A shows a spinner that creates a central oxygen-richarea while FIG. 13B shows a spinner, which creates an oxygen-richperipheral area. These diagrams are for illustration purposes only.

Other implementations of spinners may contain other numbers of fins 155,and the shape, size, and placement of the fins may vary depending uponthe shape, size and air expansion clearance of the air box of thevehicle. The air expansion clearance can be defined as the verticalclearance between the top surface of the filter and the air intake portwithin the air box. The shape, and size of the fins should be designedso that the most efficient separation of oxygen is achieved for thevolume of the air box. Placement of the spinner will depend upon thelocation of the air intake port within the air box, as will theselection of the type of spinner to use.

The proper placement of the spinner unit has to be achieved in orderthat a good (ideally, optimal) supply of the oxygen-rich air isavailable at the position of the air intake port already built into theair box cover. This placement has to be chosen along all three axes, thex and the z-axes along the horizontal surface of the filter, i.e., thefilter's length and width, as well as along the y-axis, i.e., the heightabove the filter surface where the spinner is placed. When all three ofthese parameters are correctly adjusted depending on the air box beingtargeted, an optimal oxygen-rich area can be generated at the air intakeport.

As the engine suction occurs, the air being sucked will be from acertain fairly well defined region within the air box. This region ofsuction, called the “suction range”, changes in volume as engine suctionchanges. Specifically, the suction range will become narrower relativeto the suction axis as the force increases, and therefore the volumeenclosed by the boundaries of the suction range will decrease withincreasing suction force. For efficient utilization of the spinner unit,it is important to design and to place the unit so that the oxygen-richchannel falls within the dynamics of the suction range of the air intakeport.

FIG. 13C, shows the conical suction range 158 that is mapped from theair intake port at a lower suction force, e.g., at lower engine rpm. Thefigure also shows one vane 156 of a spinner and a suitable flow pattern.FIG. 13D shows the conical suction range 159 that is mapped at a highersuction force, i.e. higher engine rpm. As described, the volume enclosedby the boundaries of the suction range is now smaller and the boundariesthemselves are closer together than at the lower suction force case. Thefigure also shows one vane 156 of a spinner and a suitable flow pattern.

FIG. 14A shows an air box 168 with the ambient air intake port 166 inthe middle of the air box. FIG. 14B shows an air box which has theintake port 166 at the side of the air box. However, a spinner creatinga central oxygen-rich column is used with an air box of the type shownin FIG. 14A and one that creates an oxygen-rich shell is to be used inthe case of an air box of the type in FIG. 14B).

The spinner could also have a mechanism for self-adjusting the angle ofinclination of the fins (FIG. 15A). In such an arrangement, the fins aresupported between an outer cylinder 170 and an inner cylinder 172 (onlyone fin is shown in the figure.) The outer cylinder 170 includes a guideslot 175, and the inner cylinder 172 includes a guide slot 177 the fin180 is supported by two fixed pivots 182, 184 and by two pins 186, 188that ride in the guide slots. This enables the fins tp to pivot in orderto change their angles of inclination as the pressure changes dependingon the suction force of the engine.

At lower engine speeds it is preferable to have a straighter path of airthrough the spinner, because the suction force is low and a significantportion of the suction force would be required to overcome the drag ofthe fins. In such a case the angle of inclination, measured from thehorizontal, should be large. As the engine speed increases, the suctionforce increases as does the volume of air flowing past the fins. Theangle of inclination would then change so that now it will be of a lowermeasure when measured from the horizontal. This lower angle of the finsin that circumstance will allow for more efficient oxygen/nitrogenseparation and will therefore result in greater overall efficiency.

The shifting of the fin angle can be achieved by a spinner that has thetop edges of the fins mounted on pivots 182, 184 and the bottom edgesthat ride along guides 175, 177. The angle of inclination 178 of thefins will self-adjust with respect to engine suction and will adjust tothe most efficient angle required for that suction force from the intakeport 190 of the air box and proportionally with the changes in pressuredue to changes in suction force of the engine. The suction force will beexerted along the suction axis 194 and the fins will ride up along theguides in proportion with the amount of force applied.

Various methods may be used to maintain the optimal fin angle dependingon the suction force applied by the engine. The fins may be designedwith the correct weights so that the suction force being applied by thespecific engine they are designed for will be sufficient for achievingthe correct fin angle. Alternately, the correct fin angle may beobtained by a system of springs attached to the fins. The springs wouldbe chosen of a correct spring constant so that the optimal fin angle canbe achieved for the suction pressure being applied by the engine. Thefin angles may also be controlled using an active control mechanism,either by a servomechanism or other means. The servomechanism canreceive its input from a pressure sensor that measures the currentpressure being applied by the engine because of suction.

An additional advantage can be achieved by an arrangement that removesthe nitrogen in the outer shell (or inner shell, as the case may be)from the air box, for example, using exhaust suction operating throughholes and valves arranged around the wall of the box. By thus increasingthe richness of oxygen in the air taken into the intake manifold, enginepower will be increased and less emission gases will be produced.

FIG. 15B shows the top view of an arrangement of a spinner 196 within anair box 292 with exhaust valves 197 to remove the nitrogen-rich air 198from the box. The figure assumes that the spinner being used produces aoxygen-rich central zone and a nitrogen-rich shell area. The valves insuch case are placed around the periphery of the air box. The values 199used may be of a simple flap type 200, which are activated purely by thepressure differentials within the air box. Alternately, valves which areelectrically activated (by solenoids or motors) and timed using a timingmechanism, either within the engine control computer, or a separatecontroller, may be employed. If the air box requires a spinner thatcreates a nitrogen-rich central zone and an oxygen-rich shell, then thevalves will need to be placed around the central area where thenitrogen-rich air is in abundance. In both cases, the effect onefficiency will be similar. For such an arrangement, an external suctionenhancer 204 can be added in order to compensate for the additionalvolume of air that will be required to be sucked in through the filter,over and above the air volume requirement of the cylinder itself. Theenhancer can either be built into the engine itself or added on to theengine or the air box as a peripheral device.

Pressure differentials can be further reduced by placing a mesh at theintake side (the ambient air side) of the filter. The mesh can be ofsquare or other shape, made of nylon or other material and the mesh sizeshould not be of a too large mesh element (or hole) area. Tested mesheshave an area of about 0.75 mm square.

Referring to FIG. 16, assume that a spinner 205 is of the kind thatcreates a central column of oxygen-rich air 206, the nitrogen isdirected toward the outer edges 207 due to the higher velocity impartedto it, and the intake port 210 is placed so that the suction is from thecentral oxygen-rich area. In this case, the oxygen-rich air 213 willhave an advantage (in terms of its position along the induction path)over the nitrogen-rich air 214 and will take the lead during entry intothe induction tube 212.

As the engine strokes and the subsequent suction forces are interleavedby dead zones, it is believed that the air profile will be as describedbelow and shown in FIGS. 17A and 17B. During the first suction cycle,oxygen will take the lead 221 into the intake port 220. This will be inthe form of an elongated bubble with the oxygen leading.

However, because the nitrogen 222 will be accelerated more, it will tendto catch up to the oxygen-rich area. As this happens 225, theoxygen-rich area will begin to envelope the nitrogen area. During thedead zone that occurs between suction cycles, the nitrogen willdecelerate faster, while oxygen will continue to travel forward becauseof its higher mass and therefore, higher momentum. This will make theoxygen once again lead the nitrogen, and will essentially create a formof an elongated bubble 227 where the walls are made of oxygen and theinside is nitrogen.

During the next stroke cycle, the nitrogen inside the bubble will onceagain try to lead the oxygen walls and will fall back with the followingdead zone. Thus, as a result of the alternating suction and non-suction(dead) zones, the nitrogen will oscillate within the bubble. For a 2000cc 4-cylinder engine, each of these elongated bubbles would have avolume of about 500 cc. With each subsequent stroke, the bubble willmove forward along the induction manifold and will essentially maintainthe profile of the bubble over its course along the induction manifold.

FIG. 17B shows one of these bubble formations with the oxygen on theoutside walls 230 and the nitrogen in the inner region 232. Theoscillatory region 234 where the nitrogen moves forward and back withinthe bubble is also shown.

FIGS. 18A and 18B are a systematic representation of the formation ofthese bubbles for two strokes of an engine. The oxygen is sucked in atthe start of the stroke 240. At the next dead zone 241, the bubblebegins to be completed in the induction tubing. This process is repeatedin the second stroke. Reference numbers 250, 252 and 254 show thedynamics of the bubble during the first of these strokes and numbers260, 262 and 264 show the dynamics during the second stroke.

It is believed that, to achieve maximum efficiency, it may be desirableto keep the volume of the area between the intake port of the air boxand the general location of the cylinder atomization points as amultiple of the volume of a single cylinder. Thus for a 2000 cc engine,where each cylinder is 500 cc, the volume of the air path between intakeport of the air box and the location of the atomization point intakesshould be of the order of either 500 cc or 1000 cc or 1500 cc. Ifhowever, the tubing is so long as to be a multiple much greater than 3or 4, it is possible that the nitrogen will break the bubble and willtake the lead over the oxygen-rich area thus negating any gains thatmight have been achieved in the engine.

It has been experimentally determined that the efficiency of the spinneris highest within a certain temperature range. We believe that this isbecause the oxygen and nitrogen molecules are in a state of heightenedexcitation and are easier to separate. Colder air is dense andexcitation of molecules is low, therefore making it harder for theseparation process. We have observed a respective drop in mileage invery cold weather Mileage falls again at higher temperatures perhapsbecause the air is rarified and separation efficiency falls again. Wehave found this range to be about 50 degrees Fahrenheit (10 degreesCelsius) to about 95 degrees F. (35 degrees C.). These temperatures areapproximate, and the range may be different. These temperatures are justa reflection of observed results.

A further enhancement would be to add a mechanism to the input side ofthe air box in order to make sure that the air supplied to the air boxlies within the optimal temperature range. The air intake can becontrolled by a flap or other mechanism that will mix warm air taken infrom a port placed closer to the engine or behind the radiator, withcolder ambient air, which will be comparatively cooler, taken in from aport which is placed away from the engine. A thermostat can be used tomove the flap so that the mix is maintained within the optimal range.For temperatures outside of the observed range, the efficiency wasobserved to be not as good as that within the range. This should onlyhappen at the higher end of the range, in very hot weather. In such acase an inter-cooler like mechanism can be employed, which cools the airinduced into the air box in order to maintain the temperature within therange. In very cold weather, no external cooling or heating mechanismwill be needed, since the heat of the engine itself will be able toprovide air that is within the range.

FIG. 19 shows an arrangement to mix air and maintain its temperaturewithin a determined optimal range. Warm air is sucked into the air boxvia a port 280 placed closer to the warm engine or behind the radiator.The ambient, relatively cooler air is sucked in via a port 281 placed sothat it takes in ambient air away from the engine area.

A flap 282 is placed so that it can move so as to be able to mix thewarm and ambient air being sucked into the box. A thermostaticcontroller 285 controls the position of the flap.

If the air being sucked in is warmer than the higher limit of thedetermined optimal range, the flap moves so that it covers, eitherwholly or partially, the inside port 283 through which warm air is pipedinto the box. As a result, more of the cool air will be allowed into thebox keeping the temperature of the mix within the optimal range. If, onthe other hand, the mix temperature is colder than the lower limit ofthe range, the flap moves to cover, either wholly or partially, theinside port 284 through which cool air is piped into the box. As aresult more of the warmer air will be allowed in, and the mix will bemaintained within the optimal range. This arrangement of the ports,piping, controller and flap may either be built into the air box or as aseparate mixing chamber placed before the air box itself.

In an example implementation, shown in FIGS. 20A, the spinner 300 ismounted directly on a filter frame 302 that contains a pleated filter304. The pleated filter and filter housing are versions that aretypically provided for insertion into the air box of a particular modelof automobile. FIGS. 20B and 20C show side and cross views of the samesample unit. The spinner of FIGS. 20A, 20B, and 20C is useful withrespect to an air box that has a center port leading to the enginebecause it produces an oxygen central column and a nitrogen outer shell.

FIGS. 21A, 21B, and 21C show a spinner that is useful for an air boxwith a side port, because it produces a central nitrogen column and anouter oxygen shell.

Although the discussion above has postulated certain mechanisms in whichthe oxygen and nitrogen in the ambient air are reorganized for thepurpose of improving the efficiency of the engine. Therefore there maybe other reasons for the success of the system that are similar to ordifferent from the ones proposed here.

Other implementations are also within the scope of the following claims.

For example, the spinner could be incorporated permanently into thefilter frame so that when the user buys a replacement filter the spinneris included. Or the spinner could be provided as a separate itemconfigured to be added to the filter when it is installed in the airbox. In other implementations, the air box could have the spinnerincorporated in it so that no modification to the filter frame would berequired.

The vanes may not have to be arranged symmetrically in a circle, norwould the surfaces of the vanes have to be planar. Other arrangements ofair directing surfaces or other mechanical or electromechanicalarrangements, whether or not vanes, could also be provided on thefilter, on the filter frame, in the air box, or at other locations andin other configurations provided that they can separate and reconfigurethe spatial relationships of the oxygen and nitrogen molecules in theair to provide more oxygen at the point and time of atomization.

The techniques described above are applicable to other kinds ofequipment that use oxygen contained in air, such as a diesel engine, afurnace, either for home heating or for other purposes such as turbinesteam generator furnaces.

For example, as shown in FIG. 22, an air box cover 290 may have aspinner unit 291 built into it. One advantage of this arrangement willbe that, when the cover is closed over the air box 292 with the filter293 inserted into it, the optimal placement of the spinner unit willautomatically be achieved. A filter built to the proper parameters maybe required to achieve good separation taking into account theparameters that have been explained earlier. This will achieve properplacement along all three axes, x, and z as well as y which is theheight at which the spinner needs to be placed above the filter surface.This will also avoid any skew in the placement along all three Cartesianplanes.

1. A method comprising downstream of a device that imparts turbulence toa flow of air that is being sucked through the device on its way to alocation where oxygen in the air is to be consumed, redistributingcomponents of the air so that when the air arrives at the location wherethe oxygen is to be consumed there is an enriched supply of oxygenavailable.
 2. The method of claim 1 in which the redistributing of thecomponents includes imparting centrifugal force to separate componentsof the air based on their relative masses.
 3. The method of claim 1 inwhich the redistributing of the components includes spinning the airthat is sucked through the device.
 4. The method of claim 3 in which thespinning comprises deflecting the air on deflection surfaces.
 5. Themethod of claim 1 in which the components of the air are redistributedbeginning at no more than a small distance from the device through whichthe air is being sucked.
 6. The method of claim 1 in which the devicethrough which the air is being sucked comprises an air filter.
 7. Themethod of claim 1 in which the location at where the oxygen is to beconsumed comprises an atomization point in an internal combustionengine.
 8. The method of claim 1 in which the components of the aircomprise oxygen and nitrogen.
 9. The method of claim 1 in which theredistribution of the components comprises causing at least one of thecomponents to tend to occupy a central cylindrical region and at leastanother of the components to tend to occupy a cylindrical shell aroundthe central cylindrical region.
 10. The method of claim 1 in which theoxygen tends to occupy the central cylindrical region.
 11. The method ofclaim 1 in which the oxygen tends to occupy the cylindrical shell.
 12. Amethod comprising increasing availability at a downstream location in anengine of oxygen contained in a supply of air by mechanically separatingoxygen and nitrogen at an upstream position in an air induction pathleading from an intake filter to the downstream position.
 13. A methodcomprising establishing regions of enhanced oxygen density in airflowing along a confined path by causing components of the air havinghigher masses to move radially away from the path along which the air isflowing; and removing at least some components of the air.
 14. A methodcomprising establishing regions of enhanced oxygen density in airflowing along a confined path by causing components of the air havinghigher masses to move radially toward the path along which the air isflowing; and removing at least some components of the air.
 15. Themethod of claim 13 in which the components are cause to move radially byimparting angular velocity to the air.
 16. The method of claim 15 inwhich the amount of angular velocity imparted depends on a pressure withwhich the air is being caused to flow along the path.
 17. The method ofclaim 1, comprising decreasing turbulence in air flowing along aconstrained path by imparting angular velocity to the air.
 18. Themethod of claim 17 in which imparting angular velocity to the aircomprises moving the air in a spiral path.
 19. The method of claim 17also comprising reducing a stage of low-amplitude, high-frequencyturbulence in the air.
 20. The method of claim 17 also comprisingreducing effects that are due to bands of turbulence produced in the airby stroking of an internal combustion engine.
 21. The method of claim 17also comprising reducing effects that are due to phase shifts withinbands of turbulence produced in the air by stroking of an internalcombustion engine.
 22. The method of claim 13 in which components of theair having higher masses are caused to move radially away from the pathalong which the air is flowing by moving the air past a structure. 23.The method of claim 14 in which components of the air having highermasses are caused to move radially toward the path along which the airis flowing by moving the air past a structure.
 24. The method of claim17 in which the angular velocity is imparted by moving the air past astructure to cause the air to move in a spiral path.
 25. The method ofclaim 19 in which the stage of low-amplitude, high-frequency turbulencein the air is reduced by moving the air past a structure
 26. The methodof claim 20 in which the effects that are due to bands of turbulenceproduced in the air by stroking of an internal combustion engine arereduced by moving the air past a structure.
 27. The method of claim 21in which the effects that are due to phase shifts within bands ofturbulence produced in the air by stroking of an internal combustionengine are reduced by moving the air past a structure.
 28. The method ofclaim 14 in which the components are caused to move radially byimparting angular velocity to the air.
 29. The method of claim 28 inwhich the amount of angular velocity imparted depends on a pressure withwhich the air is being caused to flow along the path.